The present invention relates to an apparatus for separating magnetic particles from a dispersion comprising these magnetic particles and non-magnetic particles, comprising at least one loop-like canal forming 90 to 350° of a circular arc through which the dispersion flows, at least one magnet that is movable alongside the canal and which forces the magnetic particles into at least one first outlet, and at least one second outlet through which the non-magnetic particles are forced, wherein the apparatus further comprises at least one first means for treating the dispersion or a part of the dispersion with a hydrophilic liquid and at least one second means for treating the dispersion or a part of the dispersion with a hydrophobic liquid. In addition, the present invention relates to the use of the apparatus according to the present invention for separating magnetic particles from a dispersion, comprising these magnetic particles and non-magnetic particles.
Processes and apparatuses for the separation of magnetic constituents from a dispersion comprising these and non-magnetic constituents are already known to the skilled artisan.
WO 2010/031617 A1 discloses a device for separating ferromagnetic particles from a suspension, wherein this device comprises a tubular reactor and a plurality of magnets which are arranged outside the reactor, the magnets being moveable along at least a part of the length of the reactor up to the vicinity of a particle extractor by means of rotary conveyor. The reactor is a linear tube, but is not loop-like. The cleaning of the magnetic fraction is not described.
U.S. Pat. No. 6,149,014 discloses a mill magnet separator and method for separating, wherein the separator comprises a wet drum magnetic separator capable of treating, removing tramp metal from the full flow discharge of a grinding mill having a feed box which provides overflow capacity. Separation of magnetic particles of the mentioned dispersion is achieved by fixed magnets which are arranged at the inner side of a rotating drum. The mentioned document does not disclose any specific arrangement of the apparatus in respect of gravity.
EP 0 520 917 A1 discloses a method and apparatus for magnetic separation. The apparatus comprises a magnetic separator with fixed, low intensity magnets and a rotated drum, which is surrounded by a wall to get a long magnetic separation zone. The mentioned document does not disclose any arrangement of the apparatus in respect of gravity.
U.S. Pat. No. 3,489,280 discloses a magnetic separator having field shaping poles. The separator according to this document is a drum-like separator, wherein fixed magnets are arranged at the inside of the drum which is partly surrounded by a wall. The dispersion flows through this so-built canal. Further magnets are arranged at the opposite side of this channel. The mentioned document does not disclose any arrangement of the apparatus in respect of gravity and no flushing of the magnetic separated fraction is documented.
SU 1240451 A1 discloses a separator for the separation of magnetic particles from a dispersion comprising these and non-magnetic particles by a disk-like magnetic separator, comprising fixed magnets at the outside of the disks. A canal is formed at the inside of the disks and the dispersion to be treated flows through this canal. The magnets are located at alternating positions at both sides of the disk, so that the magnetic layer is dug up by running from one side of the canal to the other side. The magnetic fraction is washed out of the disk-like canal by a clean fluid, but no washing of the magnetic fraction is documented. The mentioned document does not disclose any arrangement of the apparatus in respect of gravity.
SU 1470341 A1 discloses a separator for separating magnetic particles from dispersants comprising these and non-magnetic particles by a drum separator, wherein this drum separator comprises a long way along the drum in which a magnetic field is applied to the dispersion to be separated in order to increase yield and efficiency of magnetic separation.
WO 98/06500 discloses an apparatus and method for separating particles. This apparatus includes means for generating a rotating magnetic field such as a rotating magnetic drum. The canal through which the dispersion to be separated flows is in direct neighborhood to the magnets, wherein it is loop-like or linear. The separation is done by causing a rotation to the particles to be separated, what occurs to coarse particles, and to use this rotation as force to separate the magnetizable particles. It is not disclosed in said document that the whole reactor shall be arranged in respect to gravity in a way to improve separation of magnetic and non-magnetic particles.
EP 1524038 A1 discloses a separator for separating magnetic particles from dispersions comprising these and non-magnetic particles by a loop-like separator that is using magnetic forces to separate magnetic fraction assisted by centrifugal and gravity forces, wherein gravity forces are working across the flow direction due to the horizontal location of the loop and do not efficiently separate non-magnetic constituents from the magnetic constituents. It is not disclosed to clean the magnetic fraction in any way.